The present invention relates generally to locking mechanisms for casement windows. More specifically, the present invention relates to an improved lock handle assembly or actuator assembly for a casement window lock. Still more specifically, the present invention relates to an improved lock handle assembly or actuator assembly for installation on vinyl casement windows.
Casement windows are known. In the past, the locking of a casement window sash to a window frame has been problematic because casement window sashes have a tendency to warp with age and therefore it can be difficult to hold an entire side edge of a sash against a frame for locking purposes. Further, casement window operators typically apply the closing force to only one end of the casement window sash, e.g. the bottom end, and therefore there is a tendency for one end of the sash to engage the frame before the opposing end of the sash. As a result, the side edge of the sash that is to be locked against the frame does not engage the frame all at once thereby making the sash difficult to lock.
To overcome these problems, tie bars have been employed along the edge of the frame to lock the sash against the frame. The tie bars typically include a plurality of rollers mounted on the tie bar that engage ramped keepers spaced along the edge of the window sash. To overcome the warping problem discussed above, the rollers and keepers are appropriately spaced so that the rollers engage the keepers in a sequential manner, starting from the bottom of the sash and ending with the top of the sash. As a result, the bottom of the sash is locked first and the sequential interaction of the middle and top rollers with the middle and top keepers respectively results in the middle and top portions of the sash being pulled against the frame and locked shut.
However, due to the success and wide acceptance of such sequential locking mechanisms, these locking mechanisms are used in a variety of different windows having window frames and window sashes with a variety of dimensions and configurations. As a result, the spacing between the handle or actuator from the tie bar can vary depending upon the manufacturer and window style. Some locks are usable only with certain styles of windows and other window styles require that locks be specifically manufactured for that style. As a result, manufacturing costs can be quite high and the wide variety of locks that are required requires builders to maintain undesirably large inventories of such locks.
A further problem associated with casement window locks employing tie bars is the relative ease in which such locks can be picked. Specifically, in many prior art casement window locks, an intruder can pick the lock or force the lock open by sticking a sharp object between the sash and the frame, engaging the tie bar and pushing downward. Many casement window locks will easily open up upon the application of downward pressure on the tie bar because the handles for casement window locks are not held or retained in place and are typically free to move from the locked to the open position. Further, any attempt to employ a retainer or a latch to hold the handle in the closed or locked position would adversely affect the aesthetics of the handle and escutcheon assembly.
Still further, aesthetic demands have required the handle and escutcheon to have a relatively low profile on the inside surface of the frame. Escutcheons that protrude outwardly from the inside surface of the frame more than xc2xexe2x80x3 are not preferred by consumers and interior designers because they present a prominent appearance on the inside surface of the frame. Instead, consumers and interior designers prefer a low profile escutcheon/handle combination that attracts little notice.
However, while aesthetics demand a low profile, functionality often demands that the handle be able to rotate 180xc2x0 in order to impart a sufficient amount of linear travel to the tie bar. As a result, currently available lock handle assemblies are not able to provide a combination of a low profile for the handle and escutcheon in combination with a 180xc2x0 rotation of the handle.
Therefore, there is a need for an improved lock handle assembly for casement windows that can be utilized on a variety of window designs, that is relatively pick proof or xe2x80x9cjimmyxe2x80x9d proof and further that provides a combination of a low profile for the escutcheon and handle with a sufficient amount of lever throw resulting in a sufficient amount of linear travel for the tie bar.
The present invention provides a lock handle assembly that satisfies all of the aforenoted needs. Specifically, the lock handle assembly of the present invention is readily adaptable to a wide variety of window sizes and styles due to its use of a connecting link between the tie bar and the lock handle mechanism. Further, the lock handle assembly of the present invention includes a drive gear link which provides an xe2x80x9cover centerxe2x80x9d condition relative to the central point of rotation which makes the lock handle assembly of the present invention especially difficult to pick or jimmy. Still further, the lock handle assembly of the present invention includes an escutcheon that has a low profile on the inside surface of the window frame but still permits the handle to rotate through an arc sufficiently large enough to enable the axis where the connecting link is pivotally connected to the drive gear link to rotate through an arc sufficiently large enough to impart a linear travel to the tie bar in excess of 1.50xe2x80x3.
Specifically, in an embodiment, the present invention provides a lock handle assembly for mounting to a multi-point casement window frame having an inside surface. The lock handle assembly comprises an escutcheon for mounting to the inside surface of the frame. The escutcheon comprises an elongated body comprising an inner side facing away from the inside surface of the frame and an outer side that extends through the inside surface of the frame. The escutcheon further comprises an elongated slot for receiving a handle through the inner side of the escutcheon. The slot comprises an upper end and a lower end defined by upper and lower walls respectively. The escutcheon further comprises an exterior surface. The handle is pivotally connected to the escutcheon by a shaft having an axis that extends transversely through the slot. The shaft further connects a movable link to the handle. The shaft also passes through a fixed gear which is secured to the escutcheon. The fixed gear plate comprises an arcuate gear plate. The movable link comprises a proximal end pivotally connected to the shaft and a distal end pivotally connected to a drive gear link. The drive gear link comprises a distal end pivotally connected to the movable link and a proximate end that comprises an arcuate gear plate in mesh with the arcuate gear plate of the fixed gear plate. The distal end of the drive gear link also is pivotally connected to a connecting link at a connecting axis. The upper and lower walls and axis of the shaft define a range of rotation for the handle ranging from about 100xc2x0 to about 140xc2x0. The connecting axis rotates through an arcuate path defined by an angle ranging from greater than 140xc2x0 to less than 180xc2x0 as the handle is rotated from engagement with the upper wall to engagement with the lower wall.
In an embodiment, the fixed gear is attached to the exterior surface of the escutcheon.
In an embodiment, the fixed gear is disposed between the movable link and the exterior surface of the escutcheon.
In an embodiment, the range of rotation for the handle ranges from about 110xc2x0 to about 130xc2x0.
In an embodiment, the range of rotation for the handle is about 120xc2x0.
In an embodiment, the angle defining the arcuate path through which the connecting axis rotates ranges from about 150xc2x0 to about 170xc2x0.
In an embodiment, the angle defining the arcuate path through which the connecting axis rotates is about 160xc2x0.
In an embodiment, the arcuate gear of the fixed gear extends arcuately around the shaft and is directed towards the outer side of the escutcheon.
In an embodiment, the arcuate gear of the drive gear link is directed towards the inner side of the escutcheon.
In an embodiment, the shaft passes through the outer side of the escutcheon.
In an embodiment, the shaft is disposed exterior to the inside surface of the frame.
In an embodiment, the connecting axis moves from a first point where the handle engages the upper wall to a second point where the handle engages the lower wall, the first and second points being spaced apart by a distance that is at least 1.50xe2x80x3.
In an embodiment, the connecting axis moves from a first point where the handle engages the upper wall to a second point where the handle engages the lower wall, the first and second points being spaced apart by a distance that is about 1.89xe2x80x3 or greater than 1.89xe2x80x3.
In an embodiment, the distal end of the drive gear link is curved and the movable link is connected to the distal end of the drive gear link at a point offset from the connecting axis.
In an embodiment, the upper and lower walls extend towards each other as they extend from the inner side towards the outer side of the escutcheon.
As noted above, the use of a connecting link which connects the distal end of the drive gear link to the tie bar enables the lock handle assembly of the present invention to fit a wide variety of window sash styles and sizes.
Further, the drive gear link of the present invention provides an over center condition which makes the lock handle assembly pick or jimmy resistant. Specifically, the distal end of the drive gear link is connected to both a connecting link and the distal end of the movable link which is connected to the handle and which translates movement of the handle to both the drive gear link and connecting link. However, when the handle is in the closed position and an intruder attempts to pick or jimmy the lock by exerting a downward force on the tie bar or the connecting link, the downward force causes the distal end of the drive gear link to pivot towards the inner side of the escutcheon and the proximate end of the drive gear link to rotate away from the inside surface of the window sash (or towards the exterior of the building). This rotational force of the proximate end of the drive gear link towards the exterior of the building simply jams the drive gear link into the locked or closed position. As a result, the lock handle assembly does not rotate open as the intruder intends but is simply more tightly jammed in the locked position.
Further, the lock handle assembly is able to maintain a low profile on the inside surface of the window sash while imparting a sufficient amount of linear movement to the tie bar. That is because the shaft which connects the handle to the movable link and which provides the rotational axis of the handle is located below or exterior to the inside surface of the window sash. As a result, a portion of the handle penetrates the window sash and enables the handle/escutcheon combination to maintain a relatively low profile on the inside surface of the window sash.
Still further, a 180xc2x0 rotation of the handle is not required to impart the requisite linear travel to the tie bar. Specifically, a smaller rotation of the handle, ranging from about 100xc2x0 to about 140xc2x0, can be utilized due to the employment of the gear mechanism which comprises the arcuate gear of the fixed gear and the arcuate gear of the proximal end of the drive gear link. Thus, the employment of the gear mechanism reduces the amount of rotation required by the handle. In short, the unique combination of features provided by the lock handle assembly of the present invention enables the lock handle assembly to maintain or exhibit a low profile on the inside surface of the window sash while providing the requisite linear travel to the connecting link and therefore the tie bar.
Other objects and advantages of the present invention will become apparent to those skilled in the art upon reviewing the following detailed description, drawings and appended claims.